Metering devices are used to measure consumption of resources. Examples of metering devices include electricity meters, water meters, gas meters, steam meters, electronic volume correctors, etc.). A metering device may communicate consumption of a given resource through a pulse source communicating with a pulse-counting device via a pulse interface.
For example, FIG. 1 depicts a pulse source 102 communicating with a pulse-counting device 104 via a pulse interface 106. The pulse interface 106 may be configured to communicate a given unit of consumption by communicating a pulse corresponding to the given unit of consumption. A pulse source may be a metering device or any other device that produces pulses to indicate volume, consumption, events or alarms. The pulse-counting device 104 may be any electronic device configured to count or otherwise accumulate pulses received from the pulse-generating device. The accumulated pulses indicate total consumption. The pulse-counting device 104 may store counts and alarm events to be periodically read from the device. The pulse-counting device 104 may be included in a system such as an automated meter reading system that includes a radio transmitter for communicating alarms and other status reports.
The pulse source 102 may be geographically located in remote from the pulse-counting device 104. The pulse source 102 may connected to the pulse-counting device 104 via a cable 107 having one or more wires. These wires may experience damage from unintentional sources (e.g., storms and other natural events) and intentional source (e.g., deliberate tampering). Damage to the wires connecting the pulse interface 106 of the pulse source 102 with the pulse-counting device 104 may cause erroneous pulse counts.
Prior solutions for detecting tampering or other damage to the pulse source 102 or device including the pulse source 102 may involve connecting additional wires from the pulse interface 106 to the pulse-counting device 104. Signals on the additional wires are monitored by the pulse-counting device. For example, a magnetic tamper detection device using magnetic sensors may communicate a tamper condition detected by the magnetic sensors via additional wires connecting the sensors with the pulse-counting device. Another example of a tamper device involves detecting a “cover off” condition in which movement of one or more components (e.g., a housing or sensor) of a pulse interface 206 and/or pulse-producing device from its proper position is detected. A “cover off” condition may be detected with a magnet and reed switch, a tilt sensor, and/or a mechanical switch with spring lever, or some combination thereof. Such solutions for detecting the “cover off” condition may involve communicating one or more signals regarding the “cover off” condition-to the pulse-counting device via an additional wire. A deficiency of such solutions is that the additional wires may experience damage from unintentional sources (e.g., storms and other natural events) and intentional source (e.g., deliberate tampering).
Therefore, it is desirable to provide systems and methods for detecting tampering with a pulse-producing component of a metering device.